It is of considerable importance to manufacturers of consumer goods that their products be shipped to the end-user in a most economical, efficient, convenient and effective manner. The consumer goods are typically transported from the manufacturer in bulk, as pallet loads of stacked boxes, each of which may contain a substantial number of units of the product.
When large numbers of stackable products must be transported in large quantities to another location, the products may be arranged in a tight grouping, or array of products. Each array of products can be stacked on a pallet in layers, the pallets subsequently being transported by freight hauling compartments known in the art, e.g., for truck, rail, sea or air vessels.
While in transit, an unstable pallet can topple over leading to significant increases with respect to product delivery time and cost. When an unstable pallet topples over, the safety of those nearby is jeopardized.
Stretch wrap or stretch film is a highly stretchable plastic film that is wrapped around items. The elastic recovery keeps the items tightly bound. In contrast, shrink wrap is applied loosely around an item and shrinks tightly with heat. It is frequently used to unitize pallet loads but also may be used for bundling smaller items. The most common stretch wrap material is linear low-density polyethylene or LLDPE, which is produced by copolymerization of ethylene with alpha-olefins, the most common of which are butene, hexene and octene. The use of higher alpha-olefins (hexene or octene) gives rise to enhanced stretch film characteristics, particularly in respect of elongation at break and puncture resistance. Many films have about 500% stretch at break but are only stretched to about 100-300% in use. Once stretched, the elastic recovery is used to keep the load tight.
Shrink wrap, also shrinkwrap or shrink film, is a material made up of polymer plastic film. When heat is applied it shrinks tightly over whatever it is covering. Heat can be applied with a hand held heat gun (electric or gas) or the product and film can pass through a heat tunnel on a conveyor. Shrink wrap is commonly used as an overwrap on many types of packaging, including cartons, boxes, beverage cans and pallet loads. A variety of products may be enclosed in shrink wrap to stabilize the products, unitize them, keep them clean or add tamper resistance.
Shrink wrapping is currently the industry standard for grouping arrays of product and stretch wrap is currently the industry standard for securing loose stacks of products stacked on pallets. In shrink wrapping, the product to be shipped is wrapped with a material, usually a film, which shrinks when warmed, thereby securing the wrapping to the material and generating a secured shipping bundle. In stretch wrapping, the array of stacked products is wrapped with film that is stretched and the tension in the stretched film serving to hold the stacked products together.
Once the bundle wrapped by the stretch wrapping and shrink wrapping process has reached its shipping destination, the stretch wrap and shrink wrap material must be removed from the bundle by manual removal, including cutting, and the wrap must be discarded.
Thus, there are a number of disadvantages associated with stretch wrapping and shrink wrapping, including the use of heat to shrink the wrapping material, which is both energy intensive but may also ruin the consumer product. The machinery required for stretch wrapping and shrink wrapping requires extensive use of factory floor space. Both stretch wrapping and shrink wrapping require a large amount of material which increases overall packaging costs, as well as, poses environmental and disposal concerns.
In stretch wrapped units, vibration during shipping can cause the containers on the lower layers to shift closer together, creating an unstable palletized unit having an uneven load distribution, which puts undue stress on the containers. The damaged containers can cost the customer money and produce an unsafe situation for the customer.
Therefore, there is a need in the packaging art for an alternative to conventional packaging methods that provides an economical and efficient packaging system to connect multiples boxes together for eventual transport by providing significant materials saving and decrease in overall packaging costs.